Table 2 Means and standard deviations by symptomatic diagnostic group (subjective cognitive decline or mild cognitive impairment), sex, and Aβ/P-tau status for demographics; memory and global cognitive scores, hippocampal and total intracranial volumes; and number of APOE ε4 carriers

Age

72.59 (5.37) ^a,b

70.22 (5.46) ^a,b

70.63 (4.84) ^a,b

69.78 (5.69) ^a,b

72.35 (5.13) ^a

69.59 (5.74) ^a

71.37 (4.88) ^a

69.76 (5.52) ^a

Education

11.71 (3.84) ^a

13.00 (3.59) ^a

11.60 (3.33) ^a

11.97 (3.30) ^a

11.62 (3.49) ^a

10.71 (3.48) ^a

11.44 (3.07) ^a

10.47 (3.13) ^a

ADAS Delayed Word Recall Omissions (/10)

4.12 (1.89)

3.38 (1.89)

5.06 (3.02)

4.73 (2.80)

6.91 (2.06) ^a

5.92 (2.10) ^a

7.43 (1.81) ^a

5.24 (2.69) ^a

MMSE total score

28.35 (1.54)

28.92 (1.29)

27.88 (1.88)

27.74 (1.73)

26.65 (1.67)

27.56 (1.85)

26.84 (1.79)

27.62 (1.88)

Total intracranial volume

1.7 × 10⁶ (1.1 × 10⁵)

1.7 × 10⁶ (1.3 × 10⁵)

1.5 × 10⁶ (1.1 × 10⁵)

1.5 × 10⁶ (1.2 × 10⁵)

1.7 × 10⁶ (1.3 × 10⁵)

1.7 × 10⁶ (1.4 × 10⁵)

1.5 × 10⁶ (1.2 × 10⁵)

1.5 × 10⁶ (1.2 × 10⁵)

Total hippocampal volume

7.2 × 10³ (1.1 × 10³)

7.7 × 10³ (1.3 × 10³)

6.8 × 10³ (1.3 × 10³)

6.7 × 10³ (1.1 × 10³)

6.7 × 10³ (1.1 × 10³)

7.2 × 10³ (1.3 × 10³)

6.1 × 10³ (1.0 × 10³)

6.6 × 10³ (1.2 × 10³)

APOE ε4 carriers

21 ^a

14 ^a

17 ^a

21 ^a

55 ^a

20 ^a

46 ^a

6 ^a